The present invention relates to puffed pastry shells; and, more particularly, to a food product comprising an improved sheet of puff pastry dough, which can be baked with a food insert to provide a filled puff pastry shell, and to a process for preparing the food product.
Broadly, puff pastry dough is prepared in sheets having planar, parallel areas of fat disposed throughout, which separate large areas of dough within the sheet into a multiplicity of dough layers. Depending upon the procedure employed to prepare the puff pastry dough, the layers of dough within the sheet can extend over the entire, or only a portion of the total, surface area of the sheet. The important feature of puff pastry which distinguishes it from short or other doughs is that it rises upon baking to yield a crisp, light pastry which is characterized by a structure of parallel, horizontal flakes.
Traditionally, puff pastry dough is made by first preparing a folded sheet of dough having at least one layer of fat sandwiched between at least two layers of dough, and then alternately folding and rolling the sheet. This process results in a composite having a large number of thin layers of dough, separated from each other by interposed layers of fat. Variations on this basic concept have been made and also produce successful puff pastry doughs. For example, in U.S. Pat. No. 3,151,987 to S. F. Colby, there is described a process comprising the extrusion of alternate dough and fat layers which are then rolled, cut, laminated and rolled again to prepare a dough sheet which preferably comprises about 400 substantially continuous layers of dough, separated from each other by fat layers.
When a sheet of puff pastry dough is baked, it rises into a flaky, multi-layered product, and is ideal for use with suitable fillings to provide napoleans, turnovers, strudels, casserole covers, meat-filled pastries, and the like. And, in most applications, this desirable rising and flaking is obtained without the aid of yeast or chemical leaveners. The rising and flaking which occurs is due principally to the vaporization of moisture and the expansion of air which has been entrapped in the dough.
While the preparation of composite foods, especially those requiring pastry shells, is one of the most appealing applications of puff pastry dough, there are a number of problems which have complicated this particular use. One problem is the difficulty in preparing a baked shell having a fully-cooked, thin bottom wall surrounded by an expanded, upstanding side wall. This problem arises because the sheet of puff pastry dough tends to rise substantially uniformly, making it necessary, when using a sheet of uniform thickness, to cut out a recess in the central portion after baking. This results in both extra work and a substantial amount of waste. One approach to solving this problem is suggested in my earlier U.S. Pat. No. 3,655,402, which discloses forming a patty shell from a composite puff pastry dough preform, wherein the side and bottom forming portions are of different thicknesses. The composite is formed by laminating an annular side-forming portion to a flat sheet for forming the bottom wall. Preferably, the side-forming portion is several times the thickness of the sheet for forming the bottom. A frozen filling, encased in an open-bottomed cylindrical container, stands on the bottom member and guides the rise of the side-forming material to provide a well-shaped, crisp and flaky shell. After baking is complete, the cylindrical container is withdrawn to empty its contents into the shell.
Another problem frequently encountered in the preparation of filled puff pastry shells arises from contact of the moist filling with the surface of the dough during baking of a filled shell. Moisture in the filling tends to be absorbed by the contacting dough surfaces, with the result that the crust becomes tough and soggy and fails to rise as well as desired. Moreover, the dough underlying the filling may remain undesirably moist and be grossly undercooked. To overcome this problem, edible water-absorbing materials such as starch and flour are commonly incorporated into moist fillings. One drawback to this procedure is that fillings which require large amounts of water also require the use of large amounts of water absorbants, which may be unacceptable from an organoleptic standpoint.
According to another approach, Matz et al in U.S. Pat. Nos. 3,219,456 and 3,293,043 coat a chilled, uncooked puff pastry dough preform with acetylated monoglycerides, which form a moisture barrier between the filling and the dough.